January Weather in Trenton, United States

Last updated: June 24, 2025

In January, the average temperature in Trenton, United States hovers around -1°C (30°F). However, be prepared for a range that can plunge to a minimum of -20°C (-3°F) and reach a pleasant maximum of 18°C (64°F). Expect 17 mm (0.7 in) of precipitation over approximately 3 days, with an average humidity of 73% adding a layer of chill to the air.

January Temperature in Trenton

In January in Trenton, the average temperature is -1°C (30°F), with maximums reaching up to 18°C (64°F) and minimums dipping as low as -20°C (-3°F). Travelers should be prepared for a wide range of temperatures and dress in layers to stay comfortable.

January Weather in Trenton: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Trenton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Trenton, January typically has an average temperature of -1°C (30°F), with highs reaching up to 18°C (64°F) and lows dropping to around -20°C (-3°F).

Data source: Temperature data for Trenton generated using information from the Copernicus Climate Change Service.

January Precipitation in Trenton

In Trenton in January, the precipitation amount is 17 mm (0.7 in) over the course of 3 days.

January Precipitation Trends in Trenton

The chart displays monthly precipitation patterns in Trenton, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Trenton, January typically receives around 17 mm (0.7 inches) of precipitation spread over approximately 3 days.

Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in Trenton

In Trenton in January humidity is 73%. With an average temperature of -1°C (30°F), this humidity feels like a dense chill that seeps into your clothes, making outdoor activities feel much colder than the actual temperature suggests, so it’s essential to layer up for a comfortable travel experience.

January Average Humidity in Trenton

This chart illustrates the average monthly humidity levels in Trenton, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Trenton is approximately 73%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Trenton

In Trenton in January, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Trenton, you can check the information here.

Maximum UV Index Levels in Trenton for January

The chart shows the monthly maximum UV Index (UVI) for Trenton in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in Trenton typically reaches 3, which falls under the moderate exposure category.

Data source: Trenton January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How January Weather in Trenton Compares to Other Months

Weather in Trenton varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Trenton, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Trenton, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (30°F)	17 mm (0.7 inches)	73%	moderate
February Weather	-2°C (29°F)	16 mm (0.6 inches)	80%	moderate
March Weather	6°C (42°F)	66 mm (2.6 inches)	64%	high
April Weather	10°C (50°F)	40 mm (1.6 inches)	64%	very high
May Weather	16°C (61°F)	122 mm (4.8 inches)	76%	very high
June Weather	24°C (75°F)	55 mm (2.2 inches)	79%	extreme
July Weather	26°C (78°F)	73 mm (2.9 inches)	77%	extreme
August Weather	24°C (75°F)	65 mm (2.6 inches)	79%	very high
September Weather	21°C (69°F)	53 mm (2.1 inches)	70%	very high
October Weather	11°C (52°F)	40 mm (1.6 inches)	64%	high
November Weather	6°C (42°F)	15 mm (0.6 inches)	75%	moderate
December Weather	1°C (34°F)	21 mm (0.8 inches)	78%	moderate